A transparent member-forming composition capable of forming, for example, a fine transparent film with a high refractive index or a transparent wiring is required, aiming at its application as a microlens for an optical image forming system of an on-chip color filter used in an electronic copying machine, a solid-state imaging device, etc. or as an optical wiring to replace a copper wiring.
Among others, with the progress in miniaturization of a solid-state imaging device, the microlens used in a solid-state imaging device is required to be finer and at the same time, to have a high refractive index so as to realize more efficient light collection. For example, a composition using a silica-coated titanium oxide particle for forming a high-refractive-index microlens or forming a solid-state imaging device has been disclosed (see, for example, Patent Documents 1 and 2). In particular, the recent increase in the number of pixels is associated with the requirement that the size of one pixel be very small and light be collected more efficiently. For this purpose, a microlens having a higher refractive index is demanded. Furthermore, in order to fabricate a larger number of devices by one production, the size of the wafer used is increasing, and in this case, the coated surface state tends to be deteriorated.
On the other hand, Patent Document 3 discloses a dispersion resin having a specific structure for a color filter, which can enhance the dispersibility of an organic pigment. In addition, Patent Document 4 discloses a composition for the formation of a high-refractive-index material, in which the above-described dispersion resin having a specific structure is contained together with an inorganic fine particle.